Lithium metal secondary battery containing an electrochemically stable anode-protecting layer

Abstract

Provided is a lithium secondary battery, comprising a cathode, an anode, and a porous separator or electrolyte, wherein the anode comprises: (a) an anode active layer containing a layer of lithium or lithium alloy, in a form of a foil, coating, or multiple particles aggregated together, as an anode active material; and (b) an anode-protecting layer of a conductive sulfonated elastomer composite, disposed between the anode active layer and the separator/electrolyte; wherein the composite has from 0.01% to 40% by weight of a conductive reinforcement material and from 0.01% to 40% by weight of an inorganic filler dispersed in a sulfonated elastomeric matrix material and the protecting layer has a thickness from 1 nm to 100 μm, a fully recoverable tensile strain from 2% to 500%, a lithium ion conductivity from 10 −7 S/cm to 5×10 −2 S/cm, and an electrical conductivity from 10 −7 S/cm to 100 S/cm.

We claim: 
     
       1. A lithium metal secondary battery comprising a cathode, an anode, and a porous separator or electrolyte disposed between said cathode and said anode, wherein said anode comprises:
 a) an anode active material layer containing a layer of lithium or lithium alloy, in a form of a foil, coating, or multiple particles aggregated together, as an anode active material; and 
 b) an anode-protecting layer of a conductive sulfonated elastomer composite, disposed between said anode active material layer and said porous separator or electrolyte; wherein said conductive sulfonated elastomer composite has from 0.01% to 40% by weight of a conductive reinforcement material and from 0.01% to 40% by weight of an electrochemically stable inorganic filler dispersed in a sulfonated elastomeric matrix material, a thickness from 1 nm to 100 μm, a fully recoverable tensile strain from 2% to 500%, a lithium ion conductivity from 10 −7  S/cm to 5×10 −2  S/cm, and an electrical conductivity from 10 −7  S/cm to 100 S/cm when measured at room temperature, wherein said inorganic filler has a lithium intercalation potential from 1.1 V to 4.5 V versus Li/Li +  and is selected from an oxide, carbide, boride, nitride, sulfide, phosphide, or selenide of a transition metal, a lithiated version thereof, or a combination thereof; 
 wherein said lithium metal secondary battery does not include a lithium-sulfur battery or lithium-selenium battery. 
 
     
     
       2. The lithium metal secondary battery of  claim 1 , wherein said transition metal is selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Pd, Ag, Cd, La, Ta, W, Pt, Au, Hg, combinations thereof, and combinations thereof with Al, Ga, In, Sn, Pb, Sb, and Bi. 
     
     
       3. The lithium metal secondary battery of  claim 1 , wherein said inorganic filler is selected from nanodiscs, nanoplatelets, or nanosheets of (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenide or trichalcogenide, (c) sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, nickel, manganese, or any transition metal; (d) boron nitride, or (e) a combination thereof, wherein said nanodiscs, nanoplatelets, or nanosheets have a thickness from 1 nm to 100 nm. 
     
     
       4. The lithium metal secondary battery of  claim 1 , wherein said conductive reinforcement material is selected from graphene sheets, carbon nanotubes, carbon nanofibers, carbon or graphite fibers, expanded graphite flakes, metal nanowires, conductive polymer fibers, or a combination thereof. 
     
     
       5. The lithium metal secondary battery of  claim 1 , wherein said sulfonated elastomeric matrix material comprises a material selected from the group consisting of sulfonated version of natural polyisoprene, synthetic polyisoprene, polybutadiene, chloroprene rubber, polychloroprene, butyl rubber, styrene-butadiene rubber, nitrile rubber, ethylene propylene rubber, ethylene propylene diene rubber, metallocene-based poly(ethylene-co-octene) elastomer, poly(ethylene-co-butene) elastomer, styrene-ethylene-butadiene-styrene elastomer, epichlorohydrin rubber, polyacrylic rubber, silicone rubber, fluorosilicone rubber, perfluoroelastomers, polyether block amides, chlorosulfonated polyethylene, ethylene-vinyl acetate, thermoplastic elastomer, protein resilin, protein elastin, ethylene oxide-epichlorohydrin copolymer, polyurethane, urethane-urea copolymer, or a combination thereof. 
     
     
       6. The lithium metal secondary battery of  claim 4 , wherein said graphene sheets are selected from the group consisting of pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, nitrogenated graphene, hydrogenated graphene, doped graphene, functionalized graphene, and combinations thereof. 
     
     
       7. The lithium metal secondary battery of  claim 4 , wherein said graphene sheets comprise single-layer graphene or few-layer graphene, wherein said few-layer graphene is defined as a graphene platelet formed of less than 10 graphene planes. 
     
     
       8. The lithium metal secondary battery of  claim 4 , wherein said graphene sheets have a length or width from 5 nm to 5 μm. 
     
     
       9. The lithium metal secondary battery of  claim 1 , wherein said sulfonated elastomer composite further contains from 0.1% to 40% by weight of a lithium ion-conducting additive dispersed therein. 
     
     
       10. The lithium metal secondary battery of  claim 1 , wherein said sulfonated elastomer composite contains a lithium ion-conducting additive dispersed therein and is selected from the group consisting of Li 2 CO 3 , Li 2 O, Li 2 C 2 O 4 , LiOH, LiX, ROCO 2 Li, HCOLi, ROLi, (ROCO 2 Li) 2 , (CH 2 OCO 2 Li) 2 , Li 2 S, Li x SO y , and combinations thereof, wherein X=F, Cl, I, or Br, R=a hydrocarbon group, 0<x≤1 and 1≤y≤4. 
     
     
       11. The lithium metal secondary battery of  claim 1 , wherein said conductive reinforcement material is selected from an electron-conducting polymer, a metal particle or wire, a graphene sheet, a carbon fiber, a graphite fiber, a carbon nanofiber, a graphite nanofiber, a carbon nanotube, a graphite particle, an expanded graphite flake, an acetylene black particle, or a combination thereof. 
     
     
       12. The lithium metal secondary battery of  claim 11 , wherein said conductive reinforcement material has a thickness or diameter less than 100 nm. 
     
     
       13. The lithium metal secondary battery of  claim 1 , wherein said sulfonated elastomer composite further contains a lithium salt dispersed therein and said lithium salt is selected from the group consisting of lithium perchlorate (LiClO 4 ), lithium hexafluorophosphate (LiPF 6 ), lithium borofluoride (LiBF 4 ), lithium hexafluoroarsenide (LiAsF 6 ), lithium trifluoro-methanesulfonate (LiCF 3 SO 3 ), bis-trifluoromethyl sulfonylimide lithium (LiN(CF 3 SO 2 ) 2 ), lithium bis(oxalato)borate (LiBOB), lithium oxalyldifluoroborate (LiBF 2 C 2 O 4 ), lithium nitrate (LiNO 3 ), Li-fluoroalkyl-phosphate (LiPF 3 (CF 2 CF 3 ) 3 ), lithium bisperfluoro-ethylsulfonylimide (LiBETI), lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium trifluoromethanesulfonimide (LiTFSI), an ionic liquid-based lithium salt, or a combination thereof. 
     
     
       14. The lithium metal secondary battery of  claim 1 , wherein said sulfonated elastomer composite is mixed with an electron-conducting polymer selected from polyaniline, polypyrrole, polythiophene, polyfuran, a bi-cyclic polymer, a sulfonated derivative thereof, or a combination thereof. 
     
     
       15. The lithium metal secondary battery of  claim 1 , wherein the sulfonated elastomer composite forms a mixture or blend with a lithium ion-conducting polymer selected from the group consisting of poly(ethylene oxide) (PEO), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), poly bis-methoxy ethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), a sulfonated derivative thereof, and combinations thereof. 
     
     
       16. The lithium metal secondary battery of  claim 1 , wherein said anode-protecting layer has a thickness from 1 nm to 10 μm. 
     
     
       17. The lithium metal secondary battery of  claim 1 , wherein said cathode active material is selected from an inorganic material, an organic material, a polymeric material, or a combination thereof, and said inorganic material does not include sulfur or alkali metal polysulfide. 
     
     
       18. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from the group consisting of metal oxide, metal phosphate, metal silicide, metal selenide, transition metal sulfide, and combinations thereof. 
     
     
       19. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from the group consisting of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium-mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphate, lithium metal silicide, and combinations thereof. 
     
     
       20. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from a metal fluoride or metal chloride including the group consisting of CoF 3 , MnF 3 , FeF 3 , VF 3 , VOF 3 , TiF 3 , BiF 3 , NiF 2 , FeF 2 , CuF 2 , CuF, SnF 2 , AgF, CuCl 2 , FeCl 3 , MnCl 2 , and combinations thereof. 
     
     
       21. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from a lithium transition metal silicate, denoted as Li 2 MSiO 4  or Li 2 Ma x Mb y SiO 4 , wherein M and Ma are selected from Fe, Mn, Co, Ni, V, or VO; Mb is selected from Fe, Mn, Co, Ni, V, Ti, Al, B, Sn, or Bi; and x+y≤1. 
     
     
       22. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from the group consisting of transition metal dichalcogenide, a transition metal trichalcogenide, and combinations thereof. 
     
     
       23. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from the group consisting of TiS 2 , TaS 2 , MoS 2 , NbSe 3 , MnO 2 , CoO 2 , an iron oxide, a vanadium oxide, and combinations thereof. 
     
     
       24. The lithium metal secondary battery of  claim 18 , wherein said metal oxide comprising a vanadium oxide selected from the group consisting of VO 2 , Li x VO 2 , V 2 O 5 , Li x V 2 O 5 , V 3 O 8 , Li x V 3 O 8 , Li x V 3 O 7 , V 4 O 9 , Li x V 4 O 9 , V 6 O 13 , Li x V 6 O 13 , their doped versions, their derivatives, and combinations thereof, wherein 0.1<x<5. 
     
     
       25. The lithium metal secondary battery of  claim 18 , wherein said metal oxide or metal phosphate is selected from the group consisting of layered compound LiMO 2 , spinel compound LiM 2 O 4 , olivine compound LiMPO 4 , silicate compound Li 2 MSiO 4 , tavorite compound LiMPO 4 F, borate compound LiMBO 3 , and combination thereofs, wherein M is a transition metal or a mixture of multiple transition metals. 
     
     
       26. The lithium metal secondary battery of  claim 17 , wherein said inorganic material is selected from the group consisting of (a) bismuth selenide or bismuth telluride, (b) transition metal dichalcogenide or trichalcogenide, (c) sulfide, selenide, or telluride of niobium, zirconium, molybdenum, hafnium, tantalum, tungsten, titanium, cobalt, manganese, iron, nickel, or a transition metal; (d) boron nitride, and (e) combinations thereof. 
     
     
       27. The lithium metal secondary battery of  claim 17 , wherein said organic material or polymeric material is selected from the group consisting of poly(anthraquinonyl sulfide) (PAQS), a lithium oxocarbon, 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), poly(anthraquinonyl sulfide), pyrene-4,5,9,10-tetraone (PYT), polymer-bound PYT, quino(triazene), redox-active organic material, tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3,6,7,10,11-hexamethoxytriphenylene (HMTP), poly(5-amino-1,4-dyhydroxy anthraquinone) (PADAQ), phosphazene disulfide polymer ([(NPS 2 ) 3 ]n), lithiated 1,4,5,8-naphthalenetetraol formaldehyde polymer, hexaazatrinaphtylene (HATN), hexaazatriphenylene hexacarbonitrile (HAT(CN) 6 ), 5-benzylidene hydantoin, isatine lithium salt, pyromellitic diimide lithium salt, tetrahydroxy-p-benzoquinone derivatives (THQLi 4 ), N,N′-diphenyl-2,3,5,6-tetraketopiperazine (PHP), N,N′-diallyl-2,3,5,6-tetraketopiperazine (AP), N,N′-dipropyl-2,3,5,6-tetraketopiperazine (PRP), a thioether polymer, a quinone compound, 1,4-benzoquinone, 5,7,12,14-pentacenetetrone (PT), 5-amino-2,3-dihydro-1,4-dyhydroxy anthraquinone (ADDAQ), 5-amino-1,4-dyhydroxy anthraquinone (ADAM), calixquinone, Li 4 C 6 O 6 , Li 2 C 6 O 6 , Li 6 C 6 O 6 , and combinations thereof. 
     
     
       28. The lithium metal secondary battery of  claim 27 , wherein said thioether polymer is selected from the group consisting of poly[methanetetryl-tetra(thiomethylene)] (PMTTM), poly(2,4-dithiopentanylene) (PDTP), a polymer containing poly(ethene-1,1,2,2-tetrathiol) (PETT) as a main-chain thioether polymers, a side-chain thioether polymer having a main-chain consisting of conjugating aromatic moieties, and having a thioether side chain as a pendant, poly(2-phenyl-1,3-dithiolane) (PPDT), poly(1,4-di(1,3-dithiolan-2-yl)benzene) (PDDTB), poly(tetrahydrobenzodithiophene) (PTHBDT), poly[1,2,4,5-tetrakis(propylthio)benzene] (PTKPTB, or poly[3,4(ethylenedithio)thiophene] (PEDTT). 
     
     
       29. The lithium metal secondary battery of  claim 17 , wherein said organic material comprises a phthalocyanine compound selected from the group consisting of copper phthalocyanine, zinc phthalocyanine, tin phthalocyanine, iron phthalocyanine, lead phthalocyanine, nickel phthalocyanine, vanadyl phthalocyanine, fluorochromium phthalocyanine, magnesium phthalocyanine, manganous phthalocyanine, dilithium phthalocyanine, aluminum phthalocyanine chloride, cadmium phthalocyanine, chlorogallium phthalocyanine, cobalt phthalocyanine, silver phthalocyanine, a metal-free phthalocyanine, a chemical derivative thereof, and combinations thereof. 
     
     
       30. The lithium metal secondary battery of  claim 1 , wherein said cathode active material is in a form of nanoparticle, nanowire, nanofiber, nanotube, nanosheet, nanobelt, nanoribbon, nanodisc, nanoplatelet, or nanohorn having a thickness or diameter from 0.5 nm to 100 nm. 
     
     
       31. The lithium metal secondary battery of  claim 30 , wherein said nanoparticle, nanowire, nanofiber, nanotube, nanosheet, nanobelt, nanoribbon, nanodisc, nanoplatelet, or nanohorn is coated with or embraced by a conductive protective coating selected from a carbon material, graphene, electronically conductive polymer, conductive metal oxide, or conductive metal coating.